Remote sensing technology in measurement and analysis on the topography evolution of the radial sand ridges in South Yellow Sea

At present, Jiangsu coastal development has been raised to the level of national strategy, the priority among which is the radial sand ridges of South Yellow Sea. The development and utilization of such complicated variable radial sand ridge tidal flat lies on the comprehension of its current situation, variation characteristics and laws. The research proposed some new methods based on RS/GIS technology by which the quantitative measurement and analysis were taken on underwater topography, sand ridge and tidal creek. For example, the terrain RS images in 2006 and 1979 were overlaid to make an analysis. As regards with the sand ridges and tidal creek which are the main geomorphologic characters of the radial sand ridges, their swing positions and range were found out by the spectral measurement on the water content of tidal flat and the extraction of tidal creek medial axis respectively. Based on all of the results, the study made an analysis on the evolution process of sand ridges in 20 years. The new methods based on RS/GIS technology do not only analyze the radial sand ridges evolution laws in a more scientific and reasonable way, but also develop the application research of remote sensing technology on oceanography.